Trailer supporting and steering dolly and weight equalizer



May 19, 19534 C. l.. MILLIGAN El' AL.

TRAILER SUPPORTING rAND STEERING DOLLY AND WEIGHT EQUALIZER Filed Sept.27, 1949 M n Il. Ill/lil.

LIIXENTQR: Byglr'esejusl gin',

7 A T TOHNEX Patented May 19, 1953 UNITED TRAILER SUPPORTING ANDASTEERIN G lDOLLY AND WEIGHT EQUALIZER Charles LMHIigam, San Fernando,l:'Calii., and Clarence DnSwaim, -Wmterlo'm Iowa Application September27, 1949 'Scr'ialNa '117;96'4

other par-t voi the weight -o'i said end Aof the trailer may hesupported.

Another object is to provide a dolly and equalizer of the characterstated, including ad- ;iusting means .for equaliz'ing the weight --ofthe iront end oi the trailer Von 'the dolly and lon the tow-ing 'vehicleproportionately, asconditions require.

Another object Ais to provide -a `dolly of the character stated to whichthe trailer may be pivotally connected to enable the trailer andthedolly to Amove freely Aup :or down with .relation to each other intraveling 'over irregular roads.v

A further object is 'to provi-de .a dolly of 'the character statedincluding means, such as a jack, for lowering or lifting the hitchingend lof 'the dolly for engaging y.or disengagin'g the ball and socketjoint or other coupling, which hitches the dolly to a towing vehicle.

Other objects and advantages will appear hereinafter as thisspecincation progresses.

The invention is illustrated in the annexed drawing, which forms a partof `this-specication and in which:

Fig. 1 is a side elevation-of 'the invention-shown connected to avtrailer and a towing vehicle.

Fig. 2 is a plan view of Fig. 1.

Fig. 3 is a transverse vertical -section of the invention taken on line-3-3 of Fig. l.

Fig. 4 is a longitudinal section -taken -on line 4-4 of Fig. 2 showing adetail of construction.

Fig. 5 is an end View 4of a modification of the invention.

Fig. 6 is `a side view of one of the rocker connecting members of thedolly for pivotally connecting the dolly to a trailer.

Fig. '7 is a plan view of the shock absorber connecting arm shown keyedto the upper end of the steering post of the 'steering wheel. n i

Referring more particularly `to the drawing, -in which the samereference numerals designate the same parts in all of the views, ourinvention lncludes primarily la dolly l; an inverted channel 'beam 2;'-a supporting and steering wheel fnpon which said hea-m is turna-blymounted; foon- 'nectin'g means Il for pivotally connecting the forwardend of the tongue "5 Yof fa trailer B "to the rear 'portion of saiddollylbeam; a universal joint 'i Vfor universally connecting 'theforward end of 'the dolly I Ato 'the rear end of a towing `vehicles 8;and a v"jack screw 9 for engaging and v('lepressing the rear 5end of thedolly 'bea-m 2 to swing the forward end of lsaid beam from the'connecting means 1, Sas ya pivot, for disengaging the universal 'joint'-I to disconnect the dolly from the towing car 8, 'when vsof-desired.

The supporting and steering wheel "3 lis jour- -naled within Iadepending fork w between 'the arms lil of said fiork 'on a shaft 'i2extending through the hub hearing of said Wheel and through the lowerends fof said -ork farms fil-ii. on the outer endsofw-hieh sha'ft l?.are threaded nuts I3 against the outer sides of said fork Earri-1s,respectively, for secu-ring isaid shait sai-d -rlforli: arms. .Asteering post 1M extends upwardly Strom the upper v:end of said forklill 'through a 'bearing |25 cn the dolly 'bea-in 2, which bearingentends upwardly through :and above 4said dolly beam, and faneriend-"ahrust bearing t5 is interposed llae tweensaid'upper end xofsaid fork rand 'the lower side of said 'beam 2, which .end-thrustbearing lcomprises "a lower bearing 'member il `fon. the upper end ofthe fork 1m, .and an upper bearing Ymember lili -on 'the lower end ofthe hearing l5 and the lower :side or 'the dolly beam 12 turnanlyresting upon .said lower bearing member Ill.. through which upperbearing member AI8 and bearing '515 extends vthe steering 'post lfd.vThe upper wall 1159 o'f the inverted channel 'beam it of the dolly llis provided with two rows of bolt holes l2-0, which 4rows extendlongitndinally of 'said beam near opposite Lsides thereof,.respectively. Said bolt holes @D are suitably spaced, in each of saidrows of holes, longitudinally' -oi the beam 12, `and the `holes in eachyof said 'rows are spaced `directly opposite the holes, respectively, inthe other row transversely of said beam. By means of said bolt `holesil! the connecting means i 'for the trailer '6 may be edili-'stablysecured in different positions to the dolly beam 2 longitudinally ofsaid beam l`in the manner hereinaiter more 'fully described.

The connecting 'beams l lfor lconnecting .the tongue 5 yoi the trailerto "the dolly bea-rn4 2, includes a bearing '2l detachabiy secured tothe vupper :side of rsaid beam, a 'pivot shan 22v tending through and.iournaled in said beweeg 2I, a pair of connecting rocker members 23,formed at their forward sides with hubs 24 keyed on the end portions ofsaid pivot shaft 22, respectively, by keys 25, and flanges 26 formed onthe forward ends of the forwardly converging channel-bar side arms 21 ofthe trailer tongue 5, which flanges 26 are bolted to the rear of saidrocker members 23, respectively, by bolts 28 and nuts 29, whereby thetrailer tongue 5 is detachably and pivotally connected at its forwardend to the dolly. Nuts 30 are threaded on the ends of the pivot shaft 22against the hubs 24 of the connecting members 23 to prevent saidconnecting members from sliding off the ends of said pivot shaft. Thebearing 2I is formed with a base 3I provided with four bolt holes 32 inthe four corners, respectively, thereof, which base rests upon the upperwall I9 of the dolly channel beam 2, and through each of which boltholes and a bolt hole 20 in said wall of said beam 2 is extended a bolt33 for detachably securing said bearing to the upper wall I9 of saidchannel beam, there being a nut 34 threaded on the lower end of saidbolt against the under side of said channel beam wall I9.

On the upper end portion of the steering post I4, which extends abovethe upper end of the bearing I is keyed by a key I4 a crank arm 35resting upon the upper end of said bearing, and a nut 36 is threaded onthe upper end of said steering post I4 against said crank arm to holdsaid crank arm in position on said steering post. The rear end of aconventional pneumatic shock absorber 31 is connected by a universaljoint 38, to the outer end of said crank arm 35, while the forward endof said shock absorber is connected, by a universal joint 39, to theupper end of a vertical bracket 40 which is secured at its lower end bybolts 4I to a side Wall 42 of the channel beam 2 of the dolly I.

The jack screw 9 is mounted in a channel cross bar 45 on the trailertongue 5, which bar extends, in an inverted position, across said tongueand is welded at the lower edges of its side walls 46, at 41, to theupper walls 48 of the channel-bar side arms 21 of said trailer tongue,the jack screw 9 being threaded in and extending through the upper basewall 49 of said inverted channel cross bar 45, with the lower end ofsaid jack screw positioned directly over the dolly beam 2 near the rearend of said beam. On the upper end of said jack screw is secured asuitable handle 50 for turning said screw.

'I'he universal joint 1 may be of the conventional ball and socket typewith the socket 5I of said joint formed on the forward end of the dollybeam 2, and the ball 52 of said joint mounted on a clamp bracket 53clamped on the rear bumper 44 of the towing car 8.

In Fig. 6, showing the outer side of one of the connecting rockermembers 23, the nut 30 on the near end of the pivot shaft 22 is removedto show the key 25 which keys said rocker member on said end of saidshaft.

In Fig. 7 the nut 36 is removed from the upper end of the steering postI4 to show the key I4 for keying the inner end of the ccnnecting arm 35of the shock absorber on the upper end of the steering post I4.

The operation of our invention is as follows:

To connect the trailer 6 to the dolly I, the pivot bolt 22 beingextended through the bearing 2|, the hubs 24V of the connecting rocker'4 members 23 being fitted and keyed on the ends of said pivot bolt 22and the nuts 30 being threaded on the ends of said bolt against saidhubs 24 of said connecting rocker members 23, the flanges 26 on theforward ends of the arms 21 of the trailer tongue 5 are placed againstthe rear sides of the rocker connecting members 23, and said flanges 26are bolted by the bolts 28 and nuts 29 to said rocker connecting members23. The jack screw 9 may then be turned by its handle 50 to cause it tomove downwardly through the threaded upper wall 49 of the channel crossbar 45, and the lower end of said screw, in engagement with the upperwall I9 of the dolly beam 2, to depress the rear end of said beam andswing the forward end of said beam upwardly on the pivot shaft 22 into aposition with the socket 5I of the ball and socket joint 1 at a levelabove the level of the ball 52 of said joint on the rear of the towingcar 8, as shown in dotted lines of Fig. l of the drawing. The towing caris then backed to a position with the ball 52 on said car directly underthe socket 5I on the raised forward end of the dolly beam 2. The jackscrew 9 is then turned in a reverse direction to raise it and allow theforward end of the dolly beam 2 to swing down on pivot shaft 22 untilthe socket 5I fits over the ball 52 of the ball and socket joint 1, asshown in Fig. 1 of the drawing, thus universally connecting the forwardend of the dolly I to the rear end of the towing car 8. The ball andsocket of the universal joint 1 may then be locked together in theconventional manner by its lock 54. The jack screw 9 is also used fordepressing the rear end and swinging up the forward end of the dollybeam 2 for disengaging the universal joint 1 and disconnecting the dollyfrom the towing car, when so desired.

The connection of the trailer 6 by its tongue 5 to the 4dolly I, by thepivot shaft 22, and the universal connection of the forward end of thedolly to the rear end of the towing car 8, by the universal joint 1,places part of the weight of the forward end of the trailer on the dollyand part on the rear end of the towing car, thus equalizing the weightof the forward end of the trailer on the dolly and the towing car.

The equalization of the weight of the forward end of the trailer on thedolly and the towing car may be adjusted, as desired, by securing thepivot connection bearing 2I to the dolly beam 2 in different positionsalong said beam, which is done by extending the bearing bolts 29 throughthe bolt holes 28 in the base 21 of said bearing 2I and throughdifferent bolt holes 20, in the upper wall I9 of the dolly beam, inregistration with the bolt holes 28 in said bearing base.

In traveling over irregular road surfaces, the trailer E may swing up ordown on the pivot shaft 22 `with the weight of the forward end of thetrailer always equalized on the dolly and the towing car, and the dollywheel 3 always resting upon the surface of the road.

In the modification of our invention shown in Fig. 5 of the drawing, twoor a pair of supporting and steering wheels 55 are substituted for thesingle supporting and steering wheel 3, which wheels 55 are journaledwithin a double fork 56 side-by-side on the same axle 51 secured in thelower ends of the three fork prongs 58. The dolly beam 2 is turnablymounted upon said supporting and steering wheels 55 by means of the fork56, and the end thrust bearing I6 and the steering post I4.

The two supporting and steering wheels 55 will not shimmy, and requireno shock absorber like the shock absorber 31 for a single supporting andsteering wheel 3.

We claim:

In combination, a dolly including a wheel and a beam mounted upon saidwheel, a bearing secured to said beam, a pivot shaft turnably tted insaid bearing, connecting members on the ends, respectively, of saidpivot shaft, to which -connecting members the forward ends of the armsof a trailer tongue may be secured for pivotally connecting a trailer tosaid dolly to enable the trailer and said dolly to move up or down withrelation to each other over an irregular road surface, means foroperatively connecting the forward end of said dolly beam to a towingcar, a jack mounted on said trailer tongue, rearwardly of the pivotalconnection between the trailer and the dolly, for

engaging the upper rear part of the dolly beam for swinging the forwardend of said beam upwardly for disconnecting the connecting means betweenthe forward end of said dolly beam and said towing car.

CHARLES L. MILLIGAN. CLARENCE D. SWAIM.

References Cited in the 111e of this patent UNITED STATES PATENTS NumberName Date 2,271,304 Mulholland Jan. 27, 1942 2,344,921 McDaniel Mar. 21,1944 2,376,001 Nogie May 15, 1945 2,385,099 Nelson Sept. 18, 19452,411,009 Slimp Nov. 12, 1946 2,440,502 Etgen Apr. 27, 1948 2,496,515Bayes Feb. 7, 1950

